The invention lies in the field of optical connectors. The invention relates to a connector for detachable connection of a connector end region (through a ferrule) of an optical waveguide to another optical waveguide along a plug-in direction. The connector has a housing with a holding region for guiding the ferrule. The housing is configured such that the ferrule is guided and held in an angularly moveable way with respect to the plug-in direction. The housing also has a stress-relief region for firmly connecting the optical waveguide to the housing.
It is frequently necessary in the case of optical waveguides and, in particular, in the case of multiple optical waveguides, to connect an end region of an optical waveguide to another optical waveguide such that an optical signal can be transmitted from one optical waveguide to the next optical waveguide. For this purpose, end regions of the optical waveguides are typically held in ferrules, which, in the simplest case, grip an end of the optical waveguide to be connected and allow easy manipulation. For multiple optical waveguides that have a plurality of individual fibers, the individual fibers are held in a defined linear or matrix-shaped configuration within the ferrule so that, at a transition between two interconnected ferrules, a respective fiber of one multiple optical waveguide contacts a respective fiber of the other multiple optical waveguide. Connection of two optical waveguides creates an issue of impermissible stresses placed upon the optical fibers. Connectors have stress-relief elements in order to prevent over-stressing of an optical waveguide. The stress-relief elements of connectors are typically configured such that the optical waveguide is fixed within a housing so that forces applied to the optical waveguide are transmitted directly onto the housing without stressing the connection between the ferrule and optical waveguide.
If existing connectors are used not to make overhanging connections between optical waveguides but are, for example, used as terminals fastened on a printed circuit board, such connectors particularly lead to frequent mounting problems and/or problems in data transmission. For example, International PCT publication WO 86/02740 discloses a connector for optical waveguides. The connector has a pair of plug-in components, each holding a component having a pyramidal frustum shape. Ferrules, which are held rigidly close to one another and respectively hold the ends of the optical waveguides, are provided for connecting the optical waveguides.
European published, non-prosecuted patent application EP 0 602 726 A1 discloses a connector for optical waveguides. The connector allows the optical waveguides to be connected to a back plane. A captive ferrule, which holds the ends of the optical waveguides, is provided in order to connect the optical waveguides.
European published, non-prosecuted patent application EP 0 034 987 A1 discloses a connector for optical waveguides. In the connector, end regions of the two optical waveguides are gripped in a common flexible ferrule. The ferrule is then pressed between two sleeves to completely fill up a remaining cavity around the end regions of the two optical waveguides.
It is accordingly an object of the invention to provide a connector for detachable connection of an optical waveguide to another optical waveguide that overcomes the hereinafore-mentioned disadvantages of the heretofore-known devices of this general type and that can be used for reliably and easily connecting optical conductor cables to printed circuit boards.
In accordance with the invention, a curvature-limiting region is provided, in the region between a stress-relief region and a holding region, for limiting the outward bending of the optical waveguide given an angular displacement of a ferrule with respect to a plug-in direction. The curvature-limiting region is provided both for individual fiber ferrules and for multiple fiber ferrules. The invention is based on the fundamental idea that large losses occur with optical waveguides when an optical waveguide is curved beyond a maximum permissible curvature. Existing prior art connectors readily permit the optical waveguide to be bent such that the maximum permissible curvature is exceeded because of ferrule displacement. As such, large transmission losses occur with these connectors. Given the configuration of the curvature-limiting region of the invention, outward bending of the optical waveguide beyond a maximum permissible curvature is prevented. Thereby ensuring a reliable transmission of data in all cases.
With the foregoing and other objects in view, there is provided, in accordance with the invention, a connector for the detachable connection of one end region of an optical waveguide to another end region of another optical waveguide in a plug-in direction, the connector, including a ferrule and a housing having a holding region for holding the ferrule and for moveably guiding the ferrule in an angular direction with respect to a plug-in direction, a stress-relief region for firmly connecting an optical waveguide to the housing, and at least one curvature-limiting region, disposed in a region on the housing between the stress-relief region and the holding region, for limiting the movement of at least one of a group consisting of the optical waveguide and the ferrule, the curvature-limiting region formed such that an outward bending of the optical waveguide is limited when the ferrule is angularly displaced with respect to the plug-in direction.
The curvature-limiting region may have at least one run-up wall that has a ramp-shaped cross section and is configured and disposed such that, given an angular displacement of the ferrule, the optical waveguide comes into contact at least partially in a linear fashion with at least one run-up wall. It is the linear contact between the optical waveguide and a run-up wall that ensures no occurrence of excessively high mechanical stressing on the optical waveguide given a limitation of the curvature of the optical waveguide. However, by the appropriate configuration of the run-up wall, it can be ensured that the optical waveguide assumes a predetermined maximum curvature over the entire length of the linear contact. Precisely in the case of multiple optical waveguides, a ramp of flat and bellied construction is desirable. Alternatively, a cone-shaped run-up wall can be provided for a round optical waveguide that can bend outward on all sides.
In accordance with another feature of the invention, the curvature-limiting region has at least one running wall with a ramp-shaped cross section and is configured such that an angular displacement of the ferrule causes the optical waveguide to come into contact at least partially in a linear fashion with the at least one running wall.
In the configuration of the invention, the holding region has a moveable bearing element carrying a stop end of the ferrule. The stop end for the ferrule is situated opposite that end face of the ferrule at which the optical waveguides emerge. The bearing element can be configured so at to be tiltable about an axis running transverse to the plugging direction of the connector. One way to provide the tilt is to provide bearing sites supporting the bearing element in the housing, the bearing sites preferably being configured as bearing edges or as bearing points projecting from the housing. Alternatively, the bearing element can have projecting bearing points.
In accordance with a further feature of the invention, the holding region includes a moveable bearing element having a stop end for the ferrule.
In accordance with an added feature of the invention, the bearing element is formed to be tilted about an axis disposed transverse to the plug-in direction.
In accordance with an additional feature of the invention, the housing includes bearing sites supporting the bearing element.
In accordance with yet another feature of the invention, the bearing sites are bearing edges.
In accordance with yet a further feature of the invention, the bearing sites are bearing points projecting from the housing.
In accordance with yet an added feature of the invention, the bearing element has projecting bearing points.
In a particular configuration, the bearing element is an elastically deformable plate. The bearing element can have a U-shape and be a metal component. Configuring the bearing element as an elastically deformable plate makes it possible to ensure, in a simple way, spatial displacement of the ferrule in all directions with respect to the plug-in direction. Accordingly, the deformable plate can be provided with bearing points about which the bearing element can be angularly tilted. Moreover, lateral edges of the bearing element can be set on bearing edges so that the plate can sag. It is, therefore, possible to provide a reliably operating connector in a simple way if stops are added to limit such sagging given large displacement forces.
In accordance with yet an additional feature of the invention, the bearing element is an elastically deformable plate.
In accordance with a concomitant feature of the invention, the bearing element is a U-shaped metal component.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a connector for detachable connection of an optical waveguide to another optical waveguide, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.